Document brake for document processing devices

ABSTRACT

Document processing device, especially a document printer (10, 110), has a document issuing section which has a slit-like document issuing aperture (28) and a document support (16, 116) arranged downstream of the latter in the document issuing direction. There is arranged on the document support ( 16, 116), parallel to the document issuing aperture (28), a region (50, 150) which inhibits the sliding of a document and projects beyond at least parts (42, 142) of the document support (16, 116).

BACKGROUND OF THE INVENTION

The invention relates to a document processing device, especially adocument printer, with a document issuing section which has a slot-likedocument issuing aperture and a document support arranged downstream ofthe latter in the document issuing direction.

Document processing devices of this type are, for example, documentreading or printing devices. Within such a device, a document is takenpast the processing station by transporting means. As it is transported,it is held securely, for example between pairs of rollers. After itsprocessing, the document is pushed by the transporting device out of theissuing aperture onto the document support, where it can be removedmanually by the operator. A device of this type is known for a printerfrom the reference WO 91/13765 (corresponding to U.S. Pat. Nos.5,320,437 and 5,364,196).

To achieve a high processing rate, the documents are conveyed at highspeed. As a result, when they leave the transporting device they receivesuch a thrust that they shoot far out of the issuing aperture. Longdocuments in particular then tend to fall from the document support,because their center of gravity ends up in front of the edge of thehousing.

IBM Technical Disclosure Bulletin Vol. 17, No. 5, October 1974, page1308 discloses a paper-receiving container into which sheets of paperare conveyed at high speed. On leaving a transporting device, the sheetsbutt against a flap of flexible material which protrudes from above intothe transporting path and serves the purpose of absorbing some of thekinetic energy of the sheet of paper.

SUMMARY OF THE INVENTION

It is the object of the invention to prevent issued documents fromfalling from the document support of a document processing device.

This object is achieved by a document processing device of the presentinvention, especially a document printer, having a document issuingsection which has a slot-like document issuing aperture and a documentsupport section arranged downstream of the latter in the documentissuing direction. There is arranged on the document support section,parallel to the document issuing aperture, a slide inhibiting regionwhich inhibits the sliding of a document and projects beyond at leastparts of the document support. An upper border of a front wall of alower housing part adjacent to the document support surface forms partof the document support section. A set off of the document supportsection is formed on this housing border, the surface of which set offis set back by a distance, preferably 0.5-3 mm, below the remainingdocument support surface.

The invention is based on the observation that issued documents slide onan air cushion over the document support, so their coefficient offriction with respect to the support surface is low. The application ofa slide-inhibiting means to the support surface would also do nothing tochange this. Only a raising of the smooth support surface interrupts thecarrying layer of air and the documents lands on this surface, with theresult that a slide-inhibiting means on the support can becomeeffective. A particularly good braking effect is achieved if the regionprojecting beyond the support surface has a slide-inhibiting surface. Inthis case, this region is to have the same coefficient of frictionthroughout and be parallel to the document issuing aperture, that is tosay also parallel to the leading document edge, in order to avoid anycanting of the document.

In the case of document processing devices in which documents are fed inand issued through the same aperture, that is to say in which thedocument entering aperture is identical to the document issuingaperture, documents to be fed in are usually placed initially on thedocument support and are then pushed into the document entering apertureuntil they are taken up by the transporting device. A slide-inhibitingregion on the document support hinders the manual pushing in of thedocument. In the case of document processing devices of this type, theslide-inhibiting region is preferably arranged close to the housing edgefacing the operator and parallel to this edge. The remaining surface ofthe document support close to the entry aperture is in this case to havea substantially lower coefficient of friction. The operator can theneasily reach over the region of high sliding inhibition and exert on thedocument the pressure of his hand, effecting the pushing forward, in theregion of the low coefficient of friction.

The slide-inhibiting region projecting beyond the document supportexpediently has the width of the latter. Consequently, documents of anydesired width can be processed. If documents of only one width or of fewdifferent widths are to be processed, circular elevations, so-calledbosses, which lie close to the edges of the documents suffice. Regionslying in between then have the low coefficient of friction, whichfurther facilitates the feeding in of documents.

The raised region may be formed integrally with the document support: inthe case of a support formed from a plate, by embossing a beading orhollows from the underside, in the case of a plastics injection moldingby corresponding designing of the injection mold.

The slide-inhibiting action can be achieved by roughening or by coatingwith a granular material or a plastic of a high coefficient of friction.

The raised region may also be formed by a profiled strip made of rubberor plastic which is placed into a groove in the document support or isadhesively bonded onto the latter. In this case, the profiled stripadvantageously lies in the region of a setoff, set back from the supportsurface by a small amount--preferably 0.5-3 mm--which receives the edgeof the profiled strip close to the issuing aperture. This has the effectof preventing a document butting against the lower edge of the profiledstrip.

In a further refinement of the abovementioned arrangement, the upperhousing edge is set back so far with respect to the document supportsurface that the profiled strip does not project beyond the latter. Inthis case, a document is not braked until it has shot so far over thesupport surface that it bends downward and thereby touches the profiledstrip. In the case of this arrangement, the document feeding takes placewithout any hindrance of the operator.

Further advantageous characteristics of the invention are as follows.

The border of the document support remote from the document issuingaperture is adjacent to an edge of the device housing. Theslide-inhibiting region is arranged close to the housing edge andparallel to the latter. The coefficient of friction of theslide-inhibiting region is large in comparison to the coefficient offriction of the remaining document support surface.

The slide-inhibiting region extends substantially over the width of thedocument support.

The region projecting beyond the document support surface is formed byboss-like elevations. The elevations projecting beyond the documentsupport surface are integrally formed on the document support section.

The region projecting beyond the document support surface is a profiledstrip. The profiled strip is adhesively bonded onto the document supportsection or the profiled strip is inserted in a groove in the documentsupport section.

The profiled strip has an oval cross-sectional profile. Alternatively,the profiled strip has a fastening web which can be inserted into thegroove and a mushroom head shaped upper part adjoining the fasteningweb. In this embodiment the upper part has a flatly rising flank, facingtoward the profiled strip of the entering/issuing aperture in theinstalled position, and a flank lying opposite this rising flank andfalling in the form of an arc of a circle towards the housing edge. Theradius of the arc of a circle preferably corresponds to the radius of aneighboring housing edge.

The profiled strip consists of natural rubber and has a hardness ofpreferably 45 Shore A.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the present invention which are believed to be novel,are set forth with particularity in the appended claims. The invention,together with further objects and advantages, may best be understood byreference to the following description taken in conjunction with theaccompanying drawings, in the several Figures of which like referencenumerals identify like elements, and in which:

FIG. 1 shows a sectioned side view of a document printer with a firstexemplary embodiment of the profiled strip

FIG. 2 shows a detail from FIG. 1 with a second exemplary embodiment ofthe profiled strip

FIG. 3 shows a cross section through the profiled strip according toFIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In FIG. 1, a document printer is denoted by 10. It has an upper housingpart 12 and lower housing part 14. The upper housing part 12 leaves thefront region of the lower housing part 14 exposed, which is then coveredover at the top by a document support 16. At the side, the documentsupport 16 is bounded by a document lay 18, which ensures a definedlateral position of the documents 20, 20'.

In the region of the upper housing part 12, a baffle 22 is arranged at asmall distance from the document support 16 and parallel to the latter.Document support 16 and baffle 22 form a document transporting shaft 24.The front end 26 of the baffle 22 is bent away through about 45° fromthe document support 16, with the result that an entering/issuingaperture 28 narrowing in the form of a funnel forms with the latter.

Arranged directly downstream of the funnel, seen in document enteringdirection E, in the transporting shaft 24 is a pair of transportingrollers 30, 32. Downstream thereof is a printing station 34, which in aknown way is formed by a needle printing head 36 and a printing abutment38 and is therefore not described in any more detail.

The front wall 40 of the lower housing part 14 has, close to its upperborder 42, a region 44 of greater wall thickness. The border 42 is setback with respect to the surface 46 of the document support 16 by anamount d1. An upwardly open groove 48, into which a profiled strip 50 ofan oval cross-sectional profile is inserted, is made in the region 44.The part of the profiled strip 50 lying outside the groove 48 projectsbeyond the upper border 42 by the amount d1, thus lies approximatelyflush with the document support surface 46.

The mode of operation of the document printer represented in FIG. 1 isdescribed below.

A document 20 to be processed is pushed by the operator manually in thedirection of the arrow E over the document support 16 into theentering/issuing aperture 28, until it butts against the pair of rollers30, 32. Thereupon, a drive motor (not shown) is switched on, which turnsthe transporting rollers 30, 32 in the sense of drawing the document in,whereby the document is conveyed into the printing station 34. Afterprinting, the transporting rollers are driven at high speed in theejecting direction. The document is thereby catapulted out from the pairof transporting rollers 30, 32 and thereby flies further on an aircushion over the document support 16 counter to the arrow direction E. Ashort document in this case loses speed so quickly that it still comesto rest safely on the document support. A long document, on the otherhand, has already left the document support with its leading edge whenits rear edge leaves the pair of transporting rollers 30, 32. Its ownweight in this case makes it bow downward, as is shown for the document20. It thereby comes into contact with the profiled strip 50, whichbrakes it so quickly to a standstill that its rear edge can still besupported on the baffle 22. Falling of the document 50 from the documentsupport 16 is effectively prevented as a result. An unbraked documentwould tip over the housing edge 42 and fall from the document support16. This is diagrammatically shown for a document 20' (shown bydot-dashed lines).

FIG. 2 shows the parts relevant for the invention of a second exemplaryembodiment of a document printer 110 in a sectioned side view. Thefollowing are shown: part of a document support 116, part of a lowerhousing part 114 with front wall 140, which has close to its upperborder 142 a region 144 of greater wall thickness, into which anupwardly open groove 148 is made. A profiled strip 150 is inserted insaid groove.

The upper border 142 is set back, in a way similar to in the case of thefirst exemplary embodiment shown in FIG. 1, with respect to the surface146 of the document support 116 by an amount d2. Unlike in the firstexemplary embodiment, however, the part of the profiled strip 150protruding out of the groove 148 is set back with respect to thedocument support surface 146 by an amount d3.

The leading edge of a document ejected by the transporting rollers 30,32 must in the case of the arrangement according to FIG. 2 first of allbe conveyed beyond the edge of the upper border 142 by an amountdetermined by the physical properties of the document in order that itcan be inclined so far downward that the document can be braked by theprofiled strip 150. This arrangement has the advantage when introducinga document into the document printer 110 that the profiled strip 150 isnot touched, thus its braking action does not come to bear.

FIG. 3 shows the cross-sectional profile of the profiled strip 150 inthe installed position (shown in FIG. 2) in the document printer 110.The profiled strip substantially comprises a mushroom head-like upperpart 152, which protrudes beyond the groove 148, and a fastening web154, engaging in the groove.

The underside of the upper part 152 forms a beating surface 156, whichrests snugly on the upper edge 142 of the front housing wall 140 whenthe profiled strip is installed. The flank 158 of the upper part 152facing toward the entering/issuing aperture 28 (FIG. 1) rises with aflat angle with respect to the upper border 142, in order to ensure easysliding of a document onto the profiled strip 150. The flank 160 of theupper part 152 facing away from the entering/issuing aperture has theform of an arc of a circle whose radius is adapted to the edge radiichosen on the printer housing for design reasons and technical demoldingreasons.

The fastening web 154 tapers to a point at its lower end 162 and, closeto the lower end, is provided on both sides with spreading webs 164pointing away from the tip. Above these, clearances 166 are provided inthe fastening web 154.

When inserting, the profiled strip 150 is simply to be introduced withits pointed end 162 into the groove 148 (FIG. 2). On pressing into thegroove 148, the spreading webs 164 yield slightly in the direction ofthe clearances 166. The profiled strip is pressed into the groove 148until its bearing surface 156 rests on the upper border 142 of thehousing wail 140. For pulling the profiled strip 150 out of the groove148, a significantly greater exertion of force is required, since thespreading webs 164 thereby spread out and jam against the walls of thegroove 148.

Natural rubber of a hardness of about 45 Shore A has proven to beparticularly suitable as a material for the profiled strip, because thismaterial has a high coefficient of friction and, with this hardness, theprofiled strip can be easily introduced into the groove, but on theother hand is retained securely therein.

The invention is not limited to the particular details of the apparatusdepicted and other modifications and applications are contemplated.Certain other changes may be made in the above described apparatuswithout departing from the true spirit and scope of the invention hereininvolved. It is intended, therefore, that the subject matter in theabove depiction shall be interpreted as illustrative and not in alimiting sense.

What is claimed is:
 1. A document processing device, comprising:adocument issuing section having a slot-like document issuing apertureout of which a document is ejected in a document issuing direction; adocument support section arranged downstream of the document issuingsection in the document issuing direction; the document support sectionhaving a slide inhibiting region which inhibits sliding of the document,said slide inhibiting region being parallel to said document issuingaperture; a lower housing part having a front wall with an upper border,said slide inhibiting region attached to said upper border andprojecting beyond said upper border; a document support surface on atleast a portion of a top of said lower housing part, at least saiddocument support surface and said upper border forming said documentsupport section; said upper border being offset from and lower than saiddocument support surface by a predetermined offset distance.
 2. Thedocument processing device as claimed in claim 1, wherein the upperborder of the document support section remote from the document issuingaperture is adjacent to a housing edge of the lower housing, and theslide-inhibiting region is arranged close to the housing edge andparallel to the housing edge, and wherein a coefficient of friction ofthe slide-inhibiting region is large in comparison with a coefficient offriction of the remaining document support surface.
 3. The documentprocessing device as claimed in claim 1, wherein the slide-inhibitingregion extends substantially over a width of the document supportsection.
 4. The document processing device as claimed in claim 1,wherein the slide inhibiting region is formed by boss-like elevations.5. The document processing device as claimed in claim 4, wherein theelevations are integrally formed on the document support section.
 6. Thedocument processing device as claimed in claim 1, wherein the slideinhibiting region projecting beyond the document support surface is aprofiled strip.
 7. The document processing device as claimed in claim 6,wherein the profiled strip is adhesively bonded onto the documentsupport section.
 8. The document processing device as claimed in claim6, wherein the profiled strip is inserted in a groove in the documentsupport section.
 9. The document processing device as claimed in claim8, wherein the profiled strip has a substantially oval cross-sectionalprofile.
 10. The document processing device as claimed in claim 8,wherein the profiled strip has a fastening web which is insertable intothe groove and has a mushroom head shaped upper part adjoining thefastening web.
 11. The document processing device as claimed in claim10, wherein the upper part has a flatly rising flank, facing toward theaperture in an installed position, and wherein the upper part has afurther flank lying opposite said rising flank and falling in the formof an arc of a circle towards the housing edge.
 12. The documentprocessing device as claimed in claim 6, wherein the profiled stripconsists of natural rubber.
 13. The document processing device asclaimed in claim 11, wherein the housing edge has a radius, and whereina radius of the arc of a circle of said flank corresponds to the radiusof the housing edge.
 14. The document processing device as claimed inclaim 1, wherein said offset distance is in the range of 0.5 mm to 3.0mm.
 15. The document processing device as claimed in claim 12, whereinthe strip has a hardness of 45 Shore A.